Although plastic pollution happens globally, the micro- (<5 mm) and macroplastic (5–150 mm) transfer of plastic to terrestrial species relevant to human consumption has not been examined. We provide first-time evidence for micro- and macroplastic transfer from soil to chickens in traditional Mayan home gardens in Southeast Mexico where waste mismanagement is common. We assessed micro- and macroplastic in soil, earthworm casts, chicken feces, crops and gizzards (used for human consumption). Microplastic concentrations increased from soil (0.87 ± 1.9 particles g⁻¹), to earthworm casts (14.8 ± 28.8 particles g⁻¹), to chicken feces (129.8 ± 82.3 particles g⁻¹). Chicken gizzards contained 10.2 ± 13.8 microplastic particles, while no microplastic was found in crops. An average of 45.82 ± 42.6 macroplastic particles were found per gizzard and 11 ± 15.3 macroplastic particles per crop, with 1–10 mm particles being significantly more abundant per gizzard (31.8 ± 27.27 particles) compared to the crop (1 ± 2.2 particles). The data show that micro- and macroplastic are capable of entering terrestrial food webs.

The Chimalapas region, in eastern Oaxaca, Mexico, holds lowland rainforests, tropical dry forests, and cloud forests typical of the Neotropics, as well as montane pine and pine-oak forests more typical of the Nearctic. Totaling more than 600,000 ha, much of the region is forested, and in a good state of preservation. The Chimalapas avifauna is by far the most diverse for any region of comparable size in the country, totalling at least 464 species in the region as a whole (with more than 300 species in the lowland rainforest) representing 44% of the bird species known from Mexico. Within the region, the humid Atlantic lowlands hold 317 species, the montane regions 113 species, and the southern dry forested lowlands 216 species. Important species present in the region include Harpy Eagle Harpia harpyja and several other large eagles, Black Penelopina nigra and probably Horned Oreophasis derbianus Guans, Scarlet Macaw Ara macao, Cinnamon-tailed Sparrow Aimophila sumichrasti, Rose-bellied Bunting Passerina rositae, and Resplendent Quetzal Pharomachrus mocinno. The area holds immense lowland rainforests and cloud forests that rank among the largest and best preserved in all of Mesoamerica, including a complete lowland-to-highland continuum, with entire watersheds preserved more or less intact.

Se estimó la distribución histórica y contemporánea para la familia Psittacidae en México utilizando la mayor base de datos integrada hasta ahora y modelos ecológicos de nicho. Los modelos se generaron mediante el algoritmo MaxEnt. Se utilizaron temperatura y precipitación y se analizó la vegetación disponible y las áreas naturales protegidas decretadas hasta 2015. Los modelos no presentaron errores de omisión y permiten contar con estimaciones actuales para cada especie. La mayor distribución se estima para Amazona albifrons y la menor para Amazona auropalliata. Los resultados indican que todas las especies han perdido hábitat, principalmente Ara macao, Amazona auropalliata y A. oratrix. Aunque los bosques tropicales predominan en su distribución, los bosques templados presentan altos porcentajes para 6 especies. La proporción de superficie protegida es superior a estimaciones del año 2000. La estimación precisa de la distribución de los psitácidos presentes en México tiene implicaciones de conservación a nivel internacional, ya que 6 especies son endémicas y 4 tendrían su mayor distribución potencial en México de acuerdo con cifras de la IUCN. Ante la pérdida de distribución, algunas especies presentan una elevada vulnerabilidad presente y futura, por lo que se debe examinar la relación entre aptitud ambiental de los modelos y patrones de abundancia poblacional. El uso de modelos de nicho ecológico para evaluar cambios en distribución asociados al cambio climático es necesario.

Protected areas are of paramount relevance to conserving wildlife and ecosystem contributions to people. Yet, their conservation success is increasingly threatened by human activities including habitat loss, climate change, pollution, and species overexploitation. Thus, understanding the underlying and proximate drivers of anthropogenic threats is urgently needed to improve protected areas’ effectiveness, especially in the biodiversity-rich tropics. We addressed this issue by analyzing expert-provided data on long-term biodiversity change (last three decades) over 14 biosphere reserves from the Mesoamerican Biodiversity Hotspot. Using multivariate analyses and structural equation modeling, we tested the influence of major socioeconomic drivers (demographic, economic, and political factors), spatial indicators of human activities (agriculture expansion and road extension), and forest landscape modifications (forest loss and isolation) as drivers of biodiversity change. We uncovered a significant proliferation of disturbance-tolerant guilds and the loss or decline of disturbance-sensitive guilds within reserves causing a “winner and loser” species replacement over time. Guild change was directly related to forest spatial changes promoted by the expansion of agriculture and roads within reserves. High human population density and low nonfarming occupation were identified as the main underlying drivers of biodiversity change. Our findings suggest that to mitigate anthropogenic threats to biodiversity within biosphere reserves, fostering human population well-being via sustainable, nonfarming livelihood opportunities around reserves is imperative.